Daft fuel prices locally

[taysidedragon]

I don't know if it's true but I was told a few years ago that when using the fuel nozzle you shouldn't press the trigger all the way back but should allow the fuel to flow at a decreased rate. The reason I was given for this is due to the petrol pump reading the flow of fuel at the nozzle but when the fuel pump is delivering at a high rate air gets mixed in with the fuel. This results in the pump meter reading both the fuel and the air  and thus you pay for air as well as fuel. If you only pull the trigger halfway back there is not so much air mixed with the fuel.
I don't know if the above is true or just an urban myth however, I don't pull the trigger right back and the fuel doesn't froth as much as when the trigger is pulled right back.
There's also the reasoning to keep the tank full to prevent evaporation. This sounds a reasonable assumption however, the fuel tank in a car takes about 5-6 gallons, that's an awful lot of weight to be carrying around using fuel to carry it (even if it is being burnt off).
Maybe someone can confirm or dispel the theories?

I'm guessing here , but I'm thinking myth for air. The fuel flow meter is in the fuel pump, not at the nozzle, so should be measuring fuel only. The frothing appearance only occurs at the nozzle exit.
My car's fuel tank is 60 litres (13 gallons in old money). Each gallon weighs roughly 10 pounds, so 130 lbs in a full tank. For that reason I only fill it up when going on a long trip. Otherwise you're carrying the equivalent of a couple of heavy bags in your boot all the time.

[Johnny4428]

I’ve always been a fill it up man. But it is very true that it carrying extra weight around for nothing. Now you have to weigh that up against an xtra trip to the service station? 😝

[Lobo]

Not wishing to sound a smart **se 😬, but the specific gravity of petrol is abouts 0.72, meaning that said UK gallon actually weighs approx 7.2 lbs. Translating this into good news means a full tank is 94 lbs… or say 4% of the car’s weight (@ 2500lbs).
Assuming your average tank is 1/2 full, you’re typically only lugging 2% of extra weight around?
Life’s too short to be hanging around forecourts!

[MrDavo]

When the World Cup was on, some journalist (with nothing better to do) worked out the decrease in mpg caused by the drag from an Engerland flag on a car roof, times the number of cars carrying one (or two), times the average miles traveled over the tournament.

The result was a staggering amount of fuel being used to lug all those flags around.

Similar with full tanks. I always fill the bikes because the range is limited anyway, in the car it depends on how well off I'm feeling, I'm more likely to fill up if I'm at a (relatively) cheap supermarket.
 
Edited to add: While we're on the subject of fuel, I've read that the reason both Red Bull cars retired at the end of Sunday's Grand Prix is suspected to be cavitation in the fuel pump and fuel lines caused by the compulsory 10% sustainable ethanol element in the fuel starting to evaporate in the heat after it was sloshing around in a nearly empty tank.

[andy120t]

imagine what the price would look like if we'd had voted for Euros..